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The effect of three anaerobic swine waste lagoons on ground water quality was investigated in the Atlantic Coastal Plain region. The lagoons studied were located on high‐water‐table soils with different textures. Ground water was sampled from wells, with unperforated casings, located at depths to 6 m and distances to 30 m from the lagoons. These samples were taken monthly from September 1974 through January 1975, and bimonthly thereafter through November 1975. Ground water also was sampled in November 1975 from shallow wells with perforated casings located at distances to 36.6 m from two of the three lagoons. Constituents determined to investigate ground water contamination were density of fecal coliforms and concentrations of Cl, Cu, Mn, NH4‐N, NO3‐N, PO4‐P, and Zn.Chloride, NH4‐N, and NO3‐N concentrations in ground water samples indicated that seepage entered ground water from each of the three lagoons. Rupture of lagoon seals leading to seepage was attributed to drying of exposed subsoil or embankment soil during recession of lagoon liquid levels and to gas release from microbial activity in soil beneath the seal. Overall, a low level of ground water contamination occurred around a lagoon that was in operation for over 8 years in Myatt very fine sandy loam with a clay subsoil, and a lagoon that was in operation 1 mo prior to this investigation in Dragston fine sandy loam with a sandy clay loam subsoil. Ground water contamination in excess of recommended drinking water standards for Cl and NO3‐N occurred around the third lagoon. This lagoon was in operation for >8 years in a disturbed area consisting of predominantly sandy surface and subsurface soil. Ground water contamination in the embankment area of this lagoon was attributed to seepage and beyond the embankment area to ground water contamination from lagoon overflow.

A loafing or sacrifice lot is an area located outside of the free stall barn, where a dairy herd spends several hours per day. Sacrifice lots are usually denuded of vegetation and have high concentrations of manure and urine that can contribute significant amounts of sediment, nutrients, and pathogens to nearby surface waters. In this study, stream water quality impacted by direct runoff from a sacrifice lot was monitored for a period of 20 months. Ambient stream water quality was monitored by grab sampling upstream and downstream of the sacrifice lot. During runoff events, stream water quality downstream of the sacrifice lot was monitored with an automatic sampler. Laboratory analyses were conducted for total suspended solids and nutrients (nitrogen and phosphorus compounds). A grass filter strip (GFS) was installed as a buffer downslope of the sacrifice lot 10 months into the study period. The impact of the buffer strip on the standardized pollutant concentrations and loads was evaluated using the non‐parametric Wilcoxon test. The Wilcoxon test indicated that there was no significant difference (α= 0.05) in the standardized yield of sediment and dissolved pollutants before and after the GFS installation, except for phosphate‐phosphorus and filtered total phosphorus concentrations, and sediment‐bound total phosphorus and total kjeldahl nitrogen loads that decreased significantly. However, load decrease could have been partially caused by the smaller rainfall volumes after the GFS installation as compared to the existing condition.

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